TMG-1 is resistant to ZYMV and WMV-2, two closely related potyviruses. Resistance to ZYMV is due to a single recessive gene (Provvidenti, 1987); however, two recessive genes appear to confer resistance to WMV-2. We sought to further characterize the resistances by studying possible linkage relationships with physiological, morphological, electromorphic, and phytopathological markers. TMG-1, WI-2757 (an inbred line susceptible to both viruses), and their F2 progeny were screened for various single gene characters that differ between the two parents. Linkages reported in the literature were also observed in this study: (1) between bitterfree (bi) and female (F), and (2) between numerous spine (ns), small spine (ss), and tuberculate (Tu). New linkages detected were between: (1) resistance to WMV-2 and F, (2) resistance to WMV-2 and ZYMV, and (3) possibly resistance to ZYMV with fusarium and ns.